Part 3 of 5: Merging semantics.

Introduces the AndroidDataMerger, MergeConflict, and UnwrittenMergedAndroidData which is the entry point in the AndroidResourceProcessing *AndroidData lifecycle.

Also, refactors the AndroidDataSet parsing of resources, making it functionally immutable.

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MOS_MIGRATED_REVID=117492690

1 files changed, 70 insertions, 0 deletions

diff --git a/src/tools/android/java/com/google/devtools/build/android/MergeConflict.java b/src/tools/android/java/com/google/devtools/build/android/MergeConflict.java
new file mode 100644
index 0000000000..2728af1fb8
--- /dev/null
+++ b/src/tools/android/java/com/google/devtools/build/android/MergeConflict.java
@@ -0,0 +1,70 @@
+// Copyright 2016 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package com.google.devtools.build.android;
+
+import com.google.common.base.MoreObjects;
+
+import java.util.Objects;
+
+/**
+ * Represents a conflict of two DataResources that share the same FullyQualifiedName.
+ */
+public class MergeConflict {
+  static final String CONFLICT_MESSAGE = "%s is provided from %s and %s";
+  private final FullyQualifiedName fullyQualifiedName;
+  private final DataResource first;
+  private final DataResource second;
+
+  private MergeConflict(
+      FullyQualifiedName fullyQualifiedName, DataResource first, DataResource second) {
+    this.fullyQualifiedName = fullyQualifiedName;
+    this.first = first;
+    this.second = second;
+  }
+
+  public static MergeConflict between(
+      FullyQualifiedName fullyQualifiedName, DataResource first, DataResource second) {
+    return new MergeConflict(fullyQualifiedName, first, second);
+  }
+
+  public String toConflictMessage() {
+    return String.format(CONFLICT_MESSAGE, fullyQualifiedName, first.source(), second.source());
+  }
+
+  public FullyQualifiedName fullyQualifiedName() {
+    return fullyQualifiedName;
+  }
+
+  @Override
+  public String toString() {
+    return MoreObjects.toStringHelper(this).add("first", first).add("second", second).toString();
+  }
+
+  @Override
+  public boolean equals(Object other) {
+    if (this == other) {
+      return true;
+    }
+    if (!(other instanceof MergeConflict)) {
+      return false;
+    }
+    MergeConflict that = (MergeConflict) other;
+    return Objects.equals(first, that.first) && Objects.equals(second, that.second);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(first, second);
+  }
+}